SphereChess is a 3D variant of the classic game of Chess. There are other ways to set up chess pieces on a sphere but this version has been optimized to eliminate singularities and make game play as close as possible to the usual game of chess.
There are a few real physical versions of this game in circulation, but if you can't wait to get your hands on one of those try this virtual version. Interested in chess game variants? Browse the incredible compilation of chess variants here.